Heat exchanger



Feb. 22, 1966 w. s. WELLS HEAT EXCHANGER Filed Sept. 16, 1964 4v Fig.2

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INVENTOR W|l||om S.Wells 4 BY wwm United States Patent M 3,236,061 HEAT EXCHANGER William S. Wells, Dallas, Tex., assignor, by mesne assignments, to Cummins Engine Company, Inc., Columbus, Ind., a corporation of Indiana Filed Sept. 16, 1964, Ser. No. 397,367 7 Claims. (Cl. 62-485) This invention relates to heat exchangers and more particularly to a heat exchanger for cooling air.

An object of this invention is to provide a new and improved heat exchanger for connection in an air circulating duct system of an air conditioning apparatus system which can be installed in the duct system without requiring a particular orientation of the heat exchanger relative to the duct system.

Another object is to provide a heat exchanger having a condensate drain tank below the cooling coils through which a cold fluid is circulated wherein the heat exchanger is provided with a closure plate movable to an upstream position relative to the flow of air through the exchanger to prevent bypassing of the air below the cooling coils through the drain tank while permitting flow of condensate from the cooling coils into the drain tank downstream of the cooling coils.

Still another object is to provide a new and improved heat exchanger having a housing connectable in a duct of the air circulating system providing a passage through which the air may circulate, a heat exchanger unit disposed in the housing above a drain tank and providing with the housing downwardly opening passages on opposite sides of the heat exchanger assembly, and a closure plate for closing one passage while opening the other as required by the direction of flow of air through the passage of the housing to prevent bypassing of the air through the tank below the heat exchanger assembly While permitting flow of condensate from the assembly into the drain tank.

Still another object is to provide a heat exchanger which is of simple economical construction and wherein the closure plate may be easily adjusted in the tank as required by the direction of flow of air through the air circulating system at the site of installation of the heat exchanger in an air conditioning system.

Additional objects and advantages of the invention will be readily apparent from the reading of the following description of a device constructed in accordance with the invention, and reference to the accompanying drawings thereof, wherein:

FIGURE 1 is a perspective view, with some parts broken away, of the heat exchanger embodying the invention;

FIGURE 2 is an end View of the heat exchanger, with some parts broken away, showing the heat exchanger connected in the duct system of an air conditioning apparatus;

FIGURE 3 is a side view, with portions broken away, of the heat exchanger;

FIGURE 4 is a fragmentary partly sectional view taken on line 44 of FIGURE 3; and

FIGURE 5 is a fragmentary sectional view taken on 55 of FIGURE 4.

Referring now to the drawings, the heat exchanger includes a housing 11 having a bottom wall 12, side walls 13 and 14 and end walls 15 and 16. The end wall 16 extends the full height of the housing while the end wall 15 extends only approximately one-fourth the height of the housing. An access panel or end cover 17 closes the end of the housing above the end wall 15 and has vertical side flanges 18 and 19 which telescope over the side walls 13 and 14, respectively, and are secured thereto in any suitable manner, as by the screws 20. The end cover is Patented Feb. 22, 1966 provided to facilitate the installation of the heat exchanger assembly 21 in the housing.

The upper end of the housing is closed by a top cover 22 whose dependent flange 23 telescopes over the upper end portions of the end cover 17, the side walls 13 and 14 and the end wall 16. The top cover is rigidly secured to the housing by screws 24 which extend through suitable apertures in its dependent flange.

The lower end portion of the removable end cover 17 and the upper end portion of the end wall 15 are provided with aligned semi-spherical slots which define circular apertures through which the inlet and outlet conduits 26 and 27, respectively, of the heat exchanger assembly extend from the interior of the housing. Suitable gaskets or grommets 28 are disposed between the conduits and the end walls.

The side walls 13 and 14 of the housing have aligned rectangular apertures or windows 30 and 31, respectively, and rectangular flanges 32 and 33 which extend outwardly of the side walls over which are telescopable the ducts 34 and 35, respectively, of an air circulating duct system through which air is moved by a suitable blower or air moving means. Such ducts may, of course, be rigidly secured in seal tight relationship to the flanges by means of suitable gaskets and screws.

An internal rectangular drain tank 35 is disposed in the housing immediately below the apertures 30 and 31 and is separated from the walls and the bottom of the housing by a suitable insulating substance 36. The drain tank has external flanges 37 at its upper end which extend outwardly over the insulation to the side and end walls of the housing. The drain tank is secured to the housing, side and end walls by screws 38. The internal surfaces of the side and end walls of the housing and the top cover may be lined with a suitable insulating substance.

The heat exchanger unit 21 includes a tube and fin assembly 39 and a pair of end plates 49 and 41 provided with apertures through which extend the tubes 42 of the assembly. The end plates support the tubes and are rigidly secured thereto in any suitable manner. The outer end portions of the end plate 49 extend over and rest upon the top flange 37 of the drain tank 35 and its side flanges 43 and 44, which extend perpendicularly from its opposite vertical edges, abut the internal surfaces of the side walls 13 and 14 respectively. The flanges of the end plate are rigidly secured to the housing side walls by screws 45 and also by the screws 24a which also secure the top cover to the side Walls. The other end plate 41 is of similar configuration with its outer end portions resting on the top flange 37 of the drain tank and its side flanges 46 and 47 abutting the internal surfaces of the walls 13 and 14, respectively, and being rigidly secured thereto by the screws 48. The tubes of the tube and fin assembly also extend through suitable apertures in the usual heat conductive plates or fins 50, and are rigidly secured thereto in good heat conductive relationship as by soldering. The fins are of substantially lesser width than the end plates 40 and 41 and are positioned in the housing spaced from the housing side walls and also from the side walls 350 and 35b of the drain tank whereby transverse openings or passages are provided on opposite sides of the tube and fin assembly through which condensate from the assembly may flow into the drain tanks.

A closure plate 51 is slidably positioned below the tube and fin unit 39 on the inturned horizontal flanges 52 and 53 of the end plates 49 and 41, respectively, for closing either the passage 54 or the passage 55 depending upon the direction of flow of air through the transverse passage P of the housing defined by the end plates 40 and 41, the closure plate 51 and the cover 22.

If the flow of air is from the right to the left, as seen in FIG URES 2 and 4, the closure plate is positioned in its extreme right hand position wherein its downward flange 61 abuts the side wall 35b of the tank and is secured against movement therefrom by one of the screws 38a which secure the tank to the side wall 14. The condensate from the tube and fin assembly then tends to flow to the left due to the force of the air moving through the passage P and flows to the drain tank through the condensate passage 54. Air flowing from upstream of the tube and fin assembly cannot bypass the tube and fin unit through the tank since the closure plate closes the passage 55 on the upstream side of the tube and fin assembly. Alternately, if the flow of air is from the left to the right, as seen in FIGURES 2 and 4, the closure plate 51 is moved to its extreme left hand position wherein its flange 62 abuts the side wall 35a of the tank and may be secured in this position wherein it closes the passage 54 by a screw 38b which also secures the tank to the end wall 13. In this case, the condensate from the tube and fin assembly tends to flow to the right, due to the force exerted thereon by the air passing through the tube and fin assembly and downwardly into the tank through the passage 55.

The condensate may drain from the drain tank through a primary drain pipe 64 at its lower end which extends through suitable aligned recesses in the tank and housing walls and may also flow through a secondary drain pipe 65 located adjacent the upper end of the tank as a safety measure to insure proper drainage in the event that the primary drain pipe 64 or any conduit connected to it becomes plugged.

The tubes 42 of the tube and fin assembly may be connected in parallel between the inlet duct conduit 26 of relatively small internal diameter and the large outlet duct or manifold 27 of relatively large external diameter in the usual manner well known to those skilled in the art.

-In use, the heat exchanger is connected between the ducts 34 and 35 of an air conditioning system of a building through which air is circulated to cool the building. The inlet conduit 26 is connected to the reservoir of the system in which is received cooled and condensed refrigerant gas while the outlet conduit 27 is connected to the compressor of the system which compresses the refrigerant gas, the compressed gas being circulated through a condenser heat exchanger, in which the compressed gas is cooled and condensed, back to the reservoir.

The particular location in the building at which the heat exchanger must be connected between the ducts 34 and 35 may require that the drain pipes and the conduits leading to the tubes be positioned in a particular orientation relative to the ducts so that the air must be circulated in a particular direction through the passage P of the heat exchanger. The closure plate can be easily moved at the sit-e of installation to the required position by removing the access panel and is then secured in such position by the screw 38a or 38b.

It will now be apparent that the slidable closure plate of the heat exchanger may be easily adjusted at the site of installation to prevent the bypassing of air being circulated through the passage P below the tube and fin assembly through the drain tank while permitting proper flow of condensate to the drain tank merely by shifting the closure plate to one position or the other. As a result, the orientation of the entire heat exchanger need not be changed which may be inconvenient or impossible if the various ducts or conduits leading to the tubes of the tube and fin unit and to the drain pipe must ext-end in a particular direction.

The foregoing description of the invention is explanatory only, and changes in the details of the construction illustrated may be made by those skilled in the art, within the scope of the appended claims, without departing from the spirit of the invention.

What is claimed and desired to be secured by Letters Patent is:

1. A heat exchanger including: a housing; a heat exchanger assembly mounted in said housing, said housing having a pair of opposed aligned apertures through which air may flow therethrough and through said assembly, said housing having a drain tank below said assembly for receiving condensate from said assembly; and a plate mounted in said housing below said assembly and movable parallel to the direction of flow of air through said housing and said assembly to position upstream of the flow of air through said assembly to prevent fiow of air through said tank below said assembly and to permit flow of condensate from said assembly to said tank downstream of the flow of air through said assembly.

2. A heat exchanger including: a housing; a heat exchanger assembly mounted in said housing having a pair of opposed aligned apertures; a heat exchanger assembly mounted in said housing between said pair of opposed apertures, air flowing through said housing between apertures flowing through said assembly, said housing having a drain tank below said assembly; and a plate movably mounted in said housing below said assembly and movable to a position upstream of the direction of flow of air through said assembly to prevent flow of air through said tank below said assembly.

3. A heat exchanger including: a housing having an air flow passage extending therethrough; a heat exchanger assembly mounted in said housing and extending across said air flow passage; a drain tank in said housing below said assembly for receiving condensate from said assembly, said assembly and said housing providing a pair of passages opening downwardly into said drain tank on opposite sides of said assembly; and a plate movably mounted in said housing below said assembly and movable between a first position and a second position, said closure plate when in said first position closing one of said pair of passages and when in said second position closing the other of said pair of passages.

4. A heat exchanger including: a housing; said housing having a pair of aligned apertures; a heat exchanger assembly mounted in said housing between said apertures, said assembly including a pair of end plates and a coil assembly extending between and mounted on said end plates, said end plates extending between said apertures and providing with said housing a passage for the flow of air through said housing and said coil assembly; a drain tank in said housing below said assembly; said coil assembly being spaced from said apertures to provide parallel passages on opposite sides of said coil opening downwardly to said drain tank; and a closure plate movably mounted for movement in said housing for selectively closing either of said parallel passages.

5. A heat exchanger including: a housing; said housing having a pair of aligned apertures; a heat exchanger assembly mounted in said housing between said apertures, said assembly including a pair of end plates and a coil assembly extending between and mounted on said end plates, said end plates extending between said apertures and providing with said housing a passage for the flow of air through said housing and said coil assembly; a drain tank in said housing below said assembly; said coil assembly being spaced from said apertures to provide parallel passages on opposite sides of said coil opening downwardly to said drain tank; and a closure plate mounted on said end plates below said coil assembly and movable perpendicularly thereto between a first position wherein said closure plate closes one of said parallel passages and a second position wherein said closure plate closes the other of said parallel passages.

6. A heat exchanger including: a housing having a passage therethrough; a drain tank in said housing below said passage; air cooling means in said housing and above said tank; and closure means below said cooling means for preventing flow'of air below said cooling means through said tank, said closure means being movable parallel to the direction of flow of air through said passage to position upstream of the direction of flow of air through said cooling means to prevent flow of air through said tank below said cooling means.

7. A heat exchanger including: a housing having a passage therethrough; a drain tank in said housing below said passage; air cooling means in said housing and above said tank; and closure means below said cooling means for preventing flow of air below said cooling means 10 through said tank.

4/1938 Anderson 165-53 5/1956 Brugler 62285 ROBERT A. OLEARY, Primary Examiner.

WILLIAM J. WYE, Examiner. 

1. A HEAT EXCHANGER INCLUDING: A HOUSING: A HEAT EXCHANGER ASSEMBLY MOUNTED IN SAID HOUSING, SAID HOUSING HAVING A PAIR OF OPPOSED ALIGNED APERTURES THROUGH WHICH AIR MAY FLOW THERETHROUGH AND THROUGH SAID ASSEMBLY, SAID HOUSING HAVING A DRAIN TANK BELOW SAID ASSEMBLY FOR RECEIVING CONDENSATE FROM SAID ASSEMBLY; AND A PLATE MOUNTED IN SAID HOUSING BELOW SAID ASSEMBLY AND MOVABLE PARALLEL TO THE DIRECTION OF FLOW OF AIR THROUGH SAID HOUSING AND SAID ASSEMBLY TO POSITION UPSTREAM OF THE FLOW OF AIR THROUGH SAID ASSEMBLY TO PREVENT FLOW OF AIR 